A variety of optical telecommunication cross connects, or, switches have been developed to facilitate switching between a plurality of optical inputs and a plurality of optical outputs. Some of the known switches have been configured as 2D N×M matrix switches. One such configuration is disclosed in U.S. Pat. No. 6,363,182 entitled “Optical Switch for Reciprocal Traffic” issued Mar. 26, 2002. In such switches, a two dimensional array of optical deflectors is used to switch signals between input and output ports.
Architectures using known steering structures, for example, at least one at the input port or the output port, or both produce varying optical path lengths. This in turn results in known 3D cross connects exhibiting varying insertion losses depending on the effective optical path length. Non-uniformity of the insertion losses is a negative in terms of system design and performance.
There continues to be a need for cross connects which exhibit substantially constant insertion losses. Preferably, uniformity of insertion loss can be achieved without adding substantial manufacturing complexity or cost to the respective cross connects or switches.